From: Winnipeg, MB
Something resembling this happened to me recently , i had no solution except resetting follow on Curiously i also had 2 TF's following the carrier TF.
Initially i had a 1 cruiser TF following the carrier TF, no issues, then in a turn i added a second cruiser TF, all were okay with fuel. But then the carrier TF instead of moving the typical mission speed hexes only moved 2 hexes. There was no logical explanation.
If any ship in any of the TFs needed fuel, all would be held up waiting for that to happen. Check fuel states of each ship before and after the turn.
Otherwise, if you set one cruiser TF to follow the Carriers and then set the other cruiser TF to follow the first one, you have a daisy chain and the AI can get confused about how to process the follow commands. This seems to happen when TF numbers are not in sequence, because the AI executes the movement phase in sequence by TF # but the follow commands may be non-sequential by TF#, creating an unsolvable loop. But having both cruiser TFs follow the Carrier TF should work.
No matter how bad a situation is, you can always make it worse. - Chris Hadfield : An Astronaut's Guide To Life On Earth